 |
The Journal of Neuroscience, February 25, 2004, 24(8):1822-1832; doi:10.1523/JNEUROSCI.3564-03.2004
Previous Article | Next Article 
Behavioral/Systems/Cognitive
Attention to Features Precedes Attention to Locations in Visual Search: Evidence from Electromagnetic Brain Responses in Humans
Jens-Max Hopf,1,2
Kai Boelmans,1
Mircea Ariel Schoenfeld,1
Steven J. Luck,3 and
Hans-Jochen Heinze1
1Department of Neurology II, Otto-von-Guericke-University, D-39120 Magdeburg, Germany, 2Leibniz-Institute for Neurobiology, D-39120 Magdeburg, Germany, and 3Department of Psychology, University of Iowa, Iowa City, Iowa 52242-1407
Single-unit recordings in macaque extrastriate cortex have shown that attentional selection of nonspatial features can operate in a location-independent manner. Here, we investigated analogous neural correlates at the neural population level in human observers by using simultaneous event-related potential (ERP) and event-related magnetic field (ERMF) recordings. The goals were to determine (1) whether task-relevant features are selected before attention is allocated to the location of the target, and (2) whether this selection reflects the locations of the relevant features. A visual search task was used in which the spatial distribution of nontarget items with attended feature values was varied independently of the location of the target. The presence of task-relevant features in a given location led to a change in ERP/ERMF activity beginning 140 msec after stimulus onset, with a neural origin in the ventral occipito-temporal cortex. This effect was independent of the location of the actual target. This effect was followed by lateralized activity reflecting the allocation of attention to the location of the target (the well known N2pc component), which began at 170 msec poststimulus. Current source localization indicated that the allocation of attention to the location of the target originated in more anterior regions of occipito-temporal cortex anterior than the feature-related effects. These findings suggest that target detection in visual search begins with the detection of task-relevant features, which then allows spatial attention to be allocated to the location of a likely target, which in turn allows the target to be positively identified.
Key words: attention; visual; search; featural; spatial; human
Received July 30, 2003;
revised December 4, 2003;
accepted December 6, 2003.
This article has been cited by other articles:

|
 |

|
 |
 
C. N. Boehler, J. K. Tsotsos, M. A. Schoenfeld, H.-J. Heinze, and J.-M. Hopf
The Center-Surround Profile of the Focus of Attention Arises from Recurrent Processing in Visual Cortex
Cereb Cortex,
August 28, 2008;
(2008)
bhn139v1.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
C. N. Boehler, M. A. Schoenfeld, H.-J. Heinze, and J.-M. Hopf
Rapid recurrent processing gates awareness in primary visual cortex
PNAS,
June 24, 2008;
105(25):
8742 - 8747.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
M. M. Muller, S. Andersen, N. J. Trujillo, P. Valdes-Sosa, P. Malinowski, and S. A. Hillyard
Feature-selective attention enhances color signals in early visual areas of the human brain
PNAS,
September 19, 2006;
103(38):
14250 - 14254.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
M. Conci, K. Gramann, H. J. Muller, and M. A. Elliott
Electrophysiological Correlates of Similarity-based Interference during Detection of Visual Forms.
J. Cogn. Neurosci.,
June 1, 2006;
18(6):
880 - 888.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
A. C. Nobre, A. Rao, and L. Chelazzi
Selective attention to specific features within objects: behavioral and electrophysiological evidence.
J. Cogn. Neurosci.,
April 1, 2006;
18(4):
539 - 561.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
J.-M. Hopf, C. N. Boehler, S. J. Luck, J. K. Tsotsos, H.-J. Heinze, and M. A. Schoenfeld
Direct neurophysiological evidence for spatial suppression surrounding the focus of attention in vision
PNAS,
January 24, 2006;
103(4):
1053 - 1058.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
J. C. Snow and J. B. Mattingley
Goal-driven selective attention in patients with right hemisphere lesions: how intact is the ipsilesional field?
Brain,
January 1, 2006;
129(1):
168 - 181.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
J. Hung, J. Driver, and V. Walsh
Visual Selection and Posterior Parietal Cortex: Effects of Repetitive Transcranial Magnetic Stimulation on Partial Report Analyzed by Bundesen's Theory of Visual Attention
J. Neurosci.,
October 19, 2005;
25(42):
9602 - 9612.
[Abstract]
[Full Text]
[PDF]
|
 |
|
|